been poking around with GNOME's desktop trying to get things setup the way i want and found a few bits i want to track:

====== Desktop Files ======
  * ''/usr/share/desktop-directories/'' and ''~/.local/share/desktop-directories/'' 
    * no longer supported with GNOME 45!! :-(  
    * only Categories supported are `Utility`, `System`, and `Sundry` (which is like "miscellaneous"). :-/
  * ''/usr/share/applications/'' and ''~/.local/share/applications/''
    * contains ''.desktop'' files that dictate the paths and metadata for apps
    * e.g., ''./org.gnome.clocks.desktop'':<code>
[Desktop Entry]
Name=Clocks
GenericName=Clocks
...
Categories=GNOME;GTK;Utility;Clock;
...
</code>
  * after mucking with any of these be sure to run ''sudo update-desktop-database''